Scraping apparatus for stills.



A. A. ASHWORTH.

SCRAPING APPARATUS FOR STILLS.

APPLICATION FILED FEB. 18. 11918.

Lwogmm Patented Apr. 15,1919.

2 SHEETSSHEET I 3n van fox A. A. ASHWORTH.

SCRAPING APPARATUS FOR STILLS.

APPLlCATION FILED FEB. 18. ms.

Patented Apr. 15,1919.

2 SHEETSSHEET 2.

Mir/f rmrf ARTHUR ALAN ASHWOBTH, 0F COFFEYVILLE, KANSAS.

soc Arrm'rus For. STILLS.

Specification of Letters Patent.

Patented Apr. 15, 1919.

Application filed February 18, 1918. Serial No. 217,861.

which the followin is a specification.

My invention re ates to scraping apparatus, adapted for use in connection wlth heavy oil stills, while in no sense restricted to this-particular use.

In the operation of the ordinary still for refining heavy oils or in cracking oils, to increase the yield of gasolene, or gasolene like products, it is found that a certain amount of carbon deposits upon the inner wall of the still, articularly upon the'lower portion or fire eet thereof. This deposit or accumulation of carbon upon the fire sheet, causes over-heating of the same, and necessitates frequent cleaning out of the still, and the removal of the deposited carbon. When the carbon is thus' deposited, it becomes more or less hard and is diflicult to remove.

As far as I am aware, no wholly satisfactory scraper for use in a still, such as a heavy oil still, of the horizontal type, has as yet been devised. One difliculty heretofore experienced in connection with the prior scraping devices is that they are incapable of operating properly in the still on account of the longitudinal seams occurring in the walls thereof, principally at the union of the fire sheet with the wall of the still. A further disadvantage of the prior devices is that the scraping elements are not unrestrained so that they can be self acting in a manner to accommodate themselves to the irregularities in the. surface of the still.

An important object of the invention is to provide scraping apparatus of the above mentioned character, which is adapted to overcome the above referred to disadvan tages and having cutting edges so constructed that they are adapted to remove the deposited carbon in a highly expeditious and reliable manner.

Other objects and advantages of the invention will be apparent during the course of the following description.

In the accompanying drawings forming a part of this specification and in which like numerals are employed to designate like parts throughout the same,

Figure l is a central vertical longitudinal sectional view through apparatus embodying my invention, parts being shown in elevation,

Fig. 2 is a front end elevation of the same,

Fig. 3 is a transverse sectional View taken on line 3-3 of Fig. 4,

Fig. 4 is an enlarged fragmentary side elevationof the scraping apparatus, and

Fig. 5 is a transverse section through the apparatus, the same being shown diagrammatically.

In the drawings, the numeral 10 designates a cylindrical horizontal casing or shell of a still, suitably arranged within the upper portion of the fire box 11 of a furnace 12. This casing has a lower fire plate 10 forming seams 11. The fire box 11 is provided at one end with an opening 13 for the passage of fuel, and at its opposite end has communication with a stack 14, preferably provided with a pipe 15 as shown.

The horizontal shell 10 has one end there- .of closed by a head 16, secured thereto by any suitable means. The opposite end of the shell is closed by a head 17, illustrated as detachably connected therewith by means of bolts 18 or the like, whereby access may be readily had to the interior of the shell when desired. The heavy oils of the still to be distilled are preferably supplied into the shell 10 through a pipe 19 having a valve (not shown) connected therein. The products of distillation preferably discharge from the shell 10 through a pipe 20, having a valve, not shown, connected therein.

My scraping apparatus comprises a horizontal shaft 21, extending longitudinally of the shell 10., and arranged concentric with relation thereto, and coinciding with the central longitudinal axis of the shell. One end of the shaft 21 is journaled in a stationary bearing22, preferably attached to the head 16, while the opposite end of this shaft is journaled within and extends through a stuffing box 23, carried by the head 17.

Rigidly secured to the shaft 21 and arranged within the shell 10 are hubs 24, having diametrically extending arms 25, secured thereto and preferably formed integral therewith.

The arms 25 are provided at their lower ends with heads 26, bolted or otherwise rigidly attached to a T-shaped beam 27, comprising horizontal and vertical webs 28 and 29, as shown.

The apparatusfurther comprises a plurality of scraping elements, each of which,

as more clearly shown in FigsI 3 and 4, cmbodies a pair of scraping blades 29', rigidly secured to a pair of transverse bridges 30 at or near the ends thereof, and with which they are preferably formed integral. I prefer to cast the blades 29 and bridges 30 of iron. Each blade has an outer face 31, which is machined to fit the surface of the still shell 10 or fire plate 10'. This machining provides a pair of cuttin edges 32 upon opposite sides of each bla e 29 and these cutting edges are disposed substantially at a right angle to the inner surface of the fire plate 10'. The machined surface 31 is disposed at substantially a right angle to the opposite side walls 33, and is somewhat softer than these side walls, as the side walls retain the hard scaly'surface of the casting. The blades 29 are arranged substantially radially with respect to the wall of the still 10. The cutting edges 32 of each blade 29' are both adapted to simultaneously contact with the wall of the still and are retained parallel to the central longitudinalaxis of the shell 10.

In order that the blades 29' may automatically adjust themselves to slight ir-- regularities occurring in' the surface of the shell 10 or the fire plate 10, it is. necessary that the same be unrestrained during their movement, within v certain limits. To accomplish this the transverse bridges 30 which taper upwardly, as shown, are provided at their apices with radially extending slots 34, which receive the vertical web 29, but are slightly larger than. the same for affording aspace thereabout, to provideplay between the bridges 30 and the web 29. It is obvious that thisslight play may be in all directions,

The scraper blades."29 are disposed in end-to-end relation, and preferably contacting relation, but they may be arranged in any relation to insure the scraping of the entire surface of the fire sheet. At the ends of the set of scrapers, are transverse pins 35, passing through the radial web-0f the T- rail 27, and serving to prevent longitudinal displacement of the scrapers.

As more clearly shown in Figs. 1 and 2, a depending crank 36- is rigidly secured to one end of the shaft 21 and has pivotal connection, at 37, with a pitman 38. This pitman is pivotally connected, as shown at 39,

,with a crank 40. The crank 40 is rigidly secured to a horizontal shaft 41, which is driven by a pulley 42, receiving its rotation from any suitable source of power. When the crank 40 is rotated, the crank 36 which is longer, is oscillated back and forth causing a corresponding movementof the scraping apparatus. It might be stated at this point that the scraping elements are oscillated entirelywithin'the transverse area ofthe fire sheet 10', and therefore are not brought in contact with the seams of the still as would be the case if they were completely rotated.

Rigidly attached to the upper ends of the arms 25 is a bar 43, servin balance the bar 27, and associated scraping elements, thereby enabling the scraping apparatus to operate smoothly.

In the operation of the apparatus, the scraping elements are oscillated entirely within the transverse area ofthe fire plate 10, and therefore do not contact with the seams 11 of the still. The scraping elements serve to remove the carbon deposits from the fire plate 10' in the form of a powder, which becomes mixed with and suspended in the residue or the oil, as the distillation progresses. By this means it is not necessary to remove the powdered carbon until the process of distillation has been continued for a suitable length of time. The residue maybe removed through the pipe '17".

It is to be understood that'the form of my invention herewith shown and described is to counterscribed, the combination with the shell of a a still adapted to be arranged in ageneral horizontal position, of ashaft extending longitudinally within the shell and concentric with relation thereto, radially extending arms secured to the shaft to be turned thereby, means to turn the shaft, a bar secured to the outer ends of the arms and extending substantially parallel with the inner surface of the shell and adapted to travel in a curved path which is concentric with the inner surface of the shell, a pluralit of bridges arranged transversely of the bar and provided with radial slots for slidably receiv ing the bar whereby the bridges are-free to partake of restricted radial movements but cannot artake of undue lateral movements with re ation to the bar, and a plurality of scrapers secured to the opposite ends of each bridge. v

2 In apparatus of the character described, the combination with the stationary shell of a still having a fire-plate with seams at the edges thereof, of scraping elements arranged to contact with the inner surface of the fire-plate, and means to oscillate the scraping elements and retain the same within shell of a still having a fire-plate, of a swinging support disposed within the shell,

scraping elements connected With the swinging support and contacting with the inner surface of the fire-plate, and means to oscillate the swinging support to cause the scraping elements to travel wholly within the transverse area of the fire-plate.

4:. In apparatus of the character described, the combination with the shell of a still, said shell being substantially circular in cross-section and adapted to vbe more or less horizontally arranged, of a shaft extending longitudinally within the shell and concentric with relation thereto, radial arms secured to the shaft to be turned thereby means to turn the shaft, a bar secured to the outer ends of the arms and extending sub stantially parallel with the-inner surface of the. shell and adapted to travel in a curved path which is concentric with the inner surface of the shell, a plurality of bridges arranged transversely of the bar and provided with radial slots for slidably receiving the bar wherebythe bridges are free to partake of restricted radial movements but cannot partake of undue lateral movements with relation to the bar, a plurality of separate blades disposed upon each side of the bar, a pair of such blades being secured to each pair of bridges, each blade being provided with a pair of substantially right-angle scraping edges.

5. In apparatus of the character described, the combination with a shell, of a shaft arranged therein and extending longitudinally thereof, a bar connected with the shaft to be turned thereby, and ascrap ing element moved by the bar, said scraping element comprising a. pair of blades having their outer faces permanently contacting with the inner side of the shell during the operation of the apparatus, and a bridge connecting the blades and having a transverse slot slidably receiving said bar.

6. In apparatus. of the character described, the combination with a shell, of a a pair of fiat blades havin .bar circumferentially of the shell, and a scraping element to .be shifted by the bar,

said scraping element comprising a pair of blades having their outer edges machined in the radius of the shell and each blade being provided at its oppositesides with substantially right-angle cutting edges, and a transverse bridge connecting the blades and having atransverse opening to receive the barhand being free from connection therewit 8. In apparatus of the character described, the combination with a shell, of a bar arranged therein, means to move the bar circumferentially of the shell, and a scraping element arranged within the shell and shifted by the bar, said scraping element being cast from iron and comprising their outer edges machined to fit the she thereby pro viding cutting edges at the opposite sides of each blade, the machined edge of each blade being disposed at substantially a rightangle to the opposite sides of the blade and being softer than said sides, and a transverse bridge connecting the blades and provided with a transverse opening receiving the bar and having no connection therewith.

In testimony whereof I affix my signature in presence of two witnesses.

ARTHUR ALAN ASHWORTI-I.

Witnesses:

Louis H. JAGKMAN, Avenues P. IRVIN. 

